Addressing Trump’s previous statements that the private central bank had created a “false economy,” Clinton said presidential candidates and sitting presidents should never comment on Fed policy because it could rattle markets.

“Another example why he shouldn’t be near the White House,” Clinton said on her plane to reporters.

“You should not be commenting on Fed actions when you are either running for president or you are president. Words have consequences. Words move markets. Words can be misinterpreted. Words can have effects on people’s 401ks, their pension funds, their stock portfolios.”

“I’m not going to comment on Trump’s comment,” Clinton continued, adding, “other than to say that he should not be trying to talk up or talk down the economy and he shouldn’t be adding the Fed to the long list of institutions and individuals that he is maligning.”

On Monday, Trump told reporters the Federal Reserve was keeping interest rates low to portray Obama in a positive light.

“They’re keeping the rates down so that everything else doesn’t go down,” Trump responded when asked about the Fed’s potential September rate hike. “We have a very false economy.”

A graphic from Zero Hedge illustrates the stark difference between one of the US’ major stock indexes, the S&P, compared to this year’s Gross Domestic Product growth expectations.

As for Clinton’s assertion that presidents shouldn’t be commenting on the Fed, Zero Hedge highlights Obama commented on Fed policy earlier this year saying he was “pleased” with the work Yellen had done.